Zobrazeno 1 - 10
of 100
pro vyhledávání: '"Pozsgay, Balazs"'
We consider spin chain models with local Hamiltonians that display weak ergodicity breaking. In these models, the majority of the eigenstates are thermal, but there is a distinguished subspace of the Hilbert space in which ergodicity is broken. We ac
Externí odkaz:
http://arxiv.org/abs/2412.13951
We consider the preparation of all the eigenstates of spin chains using quantum circuits. It is known that generic eigenstates of free-fermionic spin chains can be prepared with circuits whose depth grows only polynomially with the length of the chai
Externí odkaz:
http://arxiv.org/abs/2411.15132
The Bethe Ansatz is a method for constructing exact eigenstates of quantum-integrable spin chains. Recently, deterministic quantum algorithms, referred to as "algebraic Bethe circuits", have been developed to prepare Bethe states for the spin-1/2 XXZ
Externí odkaz:
http://arxiv.org/abs/2411.02519
Autor:
Borsi, Márton, Pozsgay, Balázs
We consider spin chain models with exotic symmetries that change the length of the spin chain. It is known that the XXZ Heisenberg spin chain at the supersymmetric point $\Delta=-1/2$ possesses such a symmetry: it is given by the supersymmetry genera
Externí odkaz:
http://arxiv.org/abs/2408.15659
We consider quantum spin chains with a hidden free fermionic structure, distinct from the Jordan-Wigner transformation and its generalizations. We express selected local operators with the hidden fermions. This way we can exactly solve the real time
Externí odkaz:
http://arxiv.org/abs/2405.20832
We calculate the correlation functions of strings of spin operators for integrable quantum circuits exactly. These observables can be used for calibration of quantum simulation platforms. We use algebraic Bethe Ansatz, in combination with computation
Externí odkaz:
http://arxiv.org/abs/2405.16070
We initiate a systematic study of integrable models for spin chains with constrained Hilbert spaces; we focus on spin-1/2 chains with the Rydberg constraint. We extend earlier results for medium-range spin chains to the constrained Hilbert space, and
Externí odkaz:
http://arxiv.org/abs/2405.15848
Publikováno v:
SciPost Phys. 17, 075 (2024)
We revisit the problem of integrability breaking in free fermionic quantum spin chains. We investigate the so-called adiabatic gauge potential (AGP), which was recently proposed as an accurate probe of quantum chaos. We also study the so-called weak
Externí odkaz:
http://arxiv.org/abs/2402.12979
Autor:
Pozsgay, Balázs
Recently multiple families of spin chain models were found, which have a free fermionic spectrum, even though they are not solvable by a Jordan-Wigner transformation. Instead, the free fermions emerge as a result of a rather intricate construction. I
Externí odkaz:
http://arxiv.org/abs/2402.02984
Autor:
Fendley, Paul, Pozsgay, Balazs
Publikováno v:
SciPost Phys. 16, 102 (2024)
The Jordan-Wigner transformation is frequently utilised to rewrite quantum spin chains in terms of fermionic operators. When the resulting Hamiltonian is bilinear in these fermions, i.e. the fermions are free, the exact spectrum follows from the eige
Externí odkaz:
http://arxiv.org/abs/2310.19897